**10. Imaging results**

#### **10.1. Aspects of MRI before the CAS**

The preliminary MRI study before CAS showed six restriction foci in diffusion in four (11.11%) patients (Table 4 and Figure 4). These foci were not recorded as NF after CAS.

A comparison between the MRI diffusion sequences acquired before and after angioplasty showed 59 NF of restriction compatible with cerebral ischemia, which were distributed in 18/36 (50%) patients (Figures 5 and 6). The average NF in the 36 patients was 1.6 NF/patient (Table

Cerebral Protection in Carotid Angioplasty – Is There a Need? Advantages and Disadvantages of...

http://dx.doi.org/10.5772/57154

165

5), and the diameter varied between 1 and 25 mm.

NF size - n (%)

pt – patient

Vascular distribution (NF1) - n (%)

NF number 59 (18 patients)

<5 mm 35 (59.33)

5 – 10 mm 19 (32.21)

>10 mm 05 (8.46)

Ipsilateral 44 (77.19)

Contralateral 13 (22.81)

**Table 5.** Characteristics of new foci (NF) of hypersignal in DWI after angioplasty of the carotid artery

**Figure 5.** Patient number 9, 59 years old, underwent right CAS. DWI before CAS (A) without images of restriction.

After CAS (B): ipsilateral NF (including primary motor rotation) and contralateral NF. Asymptomatic patient.

1 Two patients were excluded from the analysis of laterality


**Table 4.** MRI data before CAS (n = 36)

Among the restriction foci in DWI before CAS, five out of six (83.33%) were ipsilateral to the carotid artery for CAS, and only one focus was not ipsilateral to the carotid that was treated (cerebellum). All hypersignal foci in DWI before CAS occurred in patients with symptomatic stenosis.

**Figure 4.** Patient number 7, male, 60 years old, underwent angioplasty of the left carotid artery. Restriction foci in DWI in the MRI scan before CAS (A). Manifestation found in 11.11% of patients. No NF were observed after CAS (B)
